𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Coordination geometry of Cr(VI) species: Structural and spectroscopic characteristics

✍ Scribed by Maria Cieślak-Golonka; Marek Daszkiewicz

Publisher
Elsevier Science
Year
2005
Tongue
English
Weight
503 KB
Volume
249
Category
Article
ISSN
0010-8545

No coin nor oath required. For personal study only.

✦ Synopsis

In this review, the speciation of chromium(VI) entities, the key to understanding the further redox processes related to this ion, is presented and discussed. Two possible modes of Cr(VI) binding, i.e. as a centre of coordination and as a ligand, have been characterized. In contrast to the gas and solid-state phases, where coordination number four is generally preserved, the Cr(VI) coordination sphere may be more flexible and chromium(VI) forms can even be seven-coordinate in solution. In the solid state, the pseudotetrahedral stereochemistry of the [CrO 4 ] 2- species does not exclude versatility of its coordination modes, e.g. monodentate, polymeric bridging, bidentate, chelate, etc. The difficulties and various problems associated with structural aspects of Cr(VI) forms, mainly in relation to their spectroscopic properties, are shown.

📜 SIMILAR VOLUMES

Comparison of the structural characteris
Comparison of the structural characteristics of chromosome VI inSaccharomyces sensu stricto: The divergence, species-dependent features and uniqueness of saké yeasts
✍ Nakazato, Atsumi; Kadokura, Toshimori; Amano, Makoto; Harayama, Tadashi; Murakam 📂 Article 📅 1998 🏛 John Wiley and Sons 🌐 English ⚖ 251 KB

Previous studies have revealed that chromosome VI of sake ´yeasts is much larger than that of the other strains of Saccharomyces cerevisiae. Southern analysis using segments of chromosome VI of a laboratory strain as probes suggested that the nucleotide sequence of a major portion of this chromosome

Four-Coordinate Group-14 Elements in the
Four-Coordinate Group-14 Elements in the Formal Oxidation State of Zero – Syntheses, Structures, and Dynamics of [{(CO)5Cr}2Sn(L2)] and Related Species
✍ Peter Kircher; Gottfried Huttner; Katja Heinze; Berthold Schiemenz; Laszlo Zsoln 📂 Article 📅 1998 🏛 John Wiley and Sons 🌐 English ⚖ 879 KB

## NMR / Salt metathesis The sodium salts Na 2 [{(CO) 5 M} 2 EX 2 ] (M = Cr, Mo, W; E = compounds (2b, 2c) are able to rotate by a full 180°turnaround with respect to one another. This process must Ge, Sn, Pb; X = Cl, I, OOCCH 3 ) react with 2,2'-bipyridine (bipy) to form neutral compounds [{(CO)

Electrochemical oxidation of [Cr(CO)4(tm
Electrochemical oxidation of [Cr(CO)4(tmp)] to the low-spin Cr(I) species [Cr(CO)4(tmp)]+ (tmp=3,4,7,8-tetramethyl-1,10-phenanthroline): an IR, UV–Vis, and EPR spectroelectrochemical and DFT computational study of the accompanying changes in molecular and electronic structure
✍ Ian R Farrell; František Hartl; Stanislav Záliš; Matthias Wanner; Wolfgang Kaim; 📂 Article 📅 2001 🏛 Elsevier Science 🌐 English ⚖ 197 KB

The complexes [Cr(CO) 4 (phen)] and [Cr(CO) 4 (tmp)] (phen = 1,10-phenanthroline, tmp =3,4,7,8-Me 4 -phen) are electrochemically oxidized at -0.01 and -0.05 V versus Fc/Fc + to the corresponding cations. The oxidation is electrochemically reversible and chemically nearly reversible at room temperatu